Magnetic levitation and suspension have been key elements in many novel and educational objects. A levitated body is herein understood to be a body not substantially physically in contact with anything external to the body during levitation, and supported by magnetic interactions with external magnetic elements substantially below the body. A suspended body is herein understood to be a body not substantially physically in contact with anything external to the body during suspension, and supported by magnetic interactions with external magnetic elements substantially above the body. Levitated tops, as first described in U.S. Pat. No. 4,382,245 by Harrigan, and in many patents by Hones, et al such as U.S. Pat. No. 5,404,062 comprise a large base magnet for creating a cup shaped magnetic field for supporting and constraining a magnetic top, stabilized against flitting over by its spinning. Hones, in U.S. Pat. No. 5,883,454, and Favatella in U.S. Pat. No. 4,643,034 describe methods of maintaining such a top at a constant spinning rate indefinitely. These top embodiments have several shortcomings. First, they are notoriously difficult to start spinning in a stable state. Second, they are very sensitive to ambient temperature and to the horizontal orientation of the magnetic field created by the base magnet. Third, they require a large, expensive base magnet even to levitate a small top. Fourth, they are inefficient and generally need a power cord to connect them to the mains for enough power to maintain rotation. Fifth, they generally must be launched manually. Sixth, they generally rotate too fast for any graphic elements on the top to be visible to an observer. Seventh, in the case of Favatella, the outside enclosure does not rotate at all, which reduces the effectiveness of the structure as a display device.
Numerous magnetic structures and electrical circuits have been described for suspending bodies magnetically by regulating the current in an electromagnet that is creating at least part of the magnetic field that is supporting the body. Some of these embodiments are described in U.S. Pat. No. 3,815,963 by Wilk, U.S. Pat. No. 3,860,300 by Lyman, U.S. Pat. No. 4,356,772 by van der Heide, U.S. Pat. No. 4,585,282 by Bosley, U.S. Pat. No. 4,910,633 by Quinn, U.S. Pat. No. 5,093,754 by Kawashima, U.S. Pat. No. 5,168,183 by Whitehead, U.S. Pat. No. 5,467,244 by Jayawan, U.S. Pat. No. 5,638,340 by Schiefele, U.S. Pat. No. 5,692,329 by Tang, U.S. Pat. No. 5.694,412 by Iannello, U.S. Pat. No. 5,732,636 by Wang, and Japanese patents JP 7-244457, JP 7-210081, and JP 7-239652 by Hiroshi. These embodiments generally suffer from two shortcomings. First, the active circuitry for stabilizing the levitation is within a non-levitated support structure which can make this structure somewhat bulky. Second, these embodiments generally derive the power to operate the circuitry and electromagnets from sources not integral to the levitated object. The embodiments of the prior art, particularly those intended to amuse and educate the observer, can be seen as simply objects on the end of a power cord that consume energy, something like a toaster.
The present invention results from an attempt to devise an intriguing and educational magnetically supported body that derives energy needed to power the support stabilization circuitry from an ambient field of light.